The proportion of women diagnosed with breast cancer who are treated with neoadjuvant systemic therapy is increasing. Depending on the subtype, 10-75% of these patients will have a pathologic complete response. Currently breast conserving surgery with pathologic complete response is followed by radiotherapy. In this patient group risk of local recurrence is low, but radiotherapy may cause considerable morbidity.
The aim of this study is to investigate whether omitting radiotherapy is safe for patients with a node-negative breast tumor \<5cm treated with neoadjuvant systemic therapy and breast conserving surgery who achieve a pathologic complete response
